• Journal of Nutrition and Health
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• v.33 no.7
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• pp.733-738
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• 2000

The purpose of this study was to investigate the effects of green tea on gene expression of superoxide dismutase(SOD) and glutathione peroxidase(GSH-Px) in rat liver exposed to microwave. Sprague-Dawley male rats with 200$\pm$10g body weight were assigned to normal and microwave exposed groups : microwave exposed groups ; microwave exposed groups were divided two groups : microwave(MW) group which was administrated the distilled water and green tea(GT) group which was administrated the green tea extracts. The rats were irradiated with microwave at frequence of 2.45 GHz for 15 min and then the gene expression in the damaged tissue were investigated at 0.1, 3, 4,6 and 8 days after the microwave irradition to compared with the normal group. The level of SOD gene expression in MW group was lower than the normal group within 6 days but that of GT group as higher than MW group. These results may imply that green tea stimulates SOD expression and there by protecting tissues from free radicals. The GSH-Px gene was expressed a little bit lower than the normal group but that of GT group was expressed to higher lever than MW group from 4 days after irradiation. These results suggest that the administration of green tea extract may activate antioxidative gene expressions such as SOD and GSH-Px in rat and that may help to recover liver tissues from microwave damage by removing hazardous free radicals and oxidized by products from cells.

• Journal of KSNVE
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• v.9 no.1
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• pp.121-130
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• 1999

Generally, A Dynamic Absorber by using Active viscous Damping is highlighted for effective suspension system, such as improved ride comfort and handling in the market. Lately, this system based on the Sky-Hook damper theory is introduced by the name of "Active Dynamic Absorber" to us. This system has an excellent performance in contrast to Passive. Adaptive Dynamic Absorber, besides having low cost components of system, low energy consumption. light weight of system. In this viewpoint. most of car-maker will adopt this system in the near future. For this reason, we developed Dynamic Absorber by using Active viscous Damping which is equipped with continuously variable Dynamic Absorber and Control logic consisting Filter and Estimator. control apparatus of Dynamic Absorber operated by 16-bit microprocessor of high performance. variable device of viscous Damping. G-sensor so on. In this paper. several important points of development procedure for realizing this system will be described with results in which is obtained from experiment by simulation and Full car test in Proving ground. respectively.pectively.

• Journal of Nutrition and Health
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• v.20 no.1
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• pp.54-64
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• 1987

The purpose of this study is to computerize all the necessary information on the daily food value and nutritional status for individuals and groups. In this research, a FOCUS-16jXT (16 bit personal computer ) compatible with IBM-PCjXT was used, and the database files and programs were created by using the dBASEIII package. The food life evaluation system consists of 3 subsystems of Reference, Nutrition Status Assessment and Food Source. The findings are summerized a8 follows: 1. Reference: This subsystem enables users to proceed to the next step, if necessary, by describing each subsystem. 2. Nutrition Status Assessment. 1) Food Habit Assessment: This subsystem determines whether the user has a good food habit or not, based on the answers for ten questions about daily food life. 2) Obesity Assessment: This subsystem calculates Broca index, which is used as a indicator of obesity. 3) Nutrient Intakes: When personal data such as age, sex, weight, height and food consumptions are input, it is possible to calculate the followings. i) Comparison between the amounts intaked and the recommended dietary daily allowances of various nutrients ii) Nutrient intakes from each food group and their composition rates for the nutrients iii) Nutrient intakes per unit body surface area iv) Composition of lipid intake 3. Food Sources: The appropriate food sources for the lacking nutrients will be recommended to the subjects.

• Journal of KSNVE
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• v.5 no.1
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• pp.107-115
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• 1995

An analytical model for drillstring axial vibration is proposed. The drillstring is modelled as an equivalent stepwise uniform bar, and the bottom boundary is modelled asa spring and a damper which depend on WOB(weight on bit). The effect of tool joints and the effect of surrounding layers, such as mud and formation, are evaluated theoretically. To investigate the bottom boundary condition, a forced axial vibration testing technique was developed and the tests with a typical drillstring were performed at various WOB's. The results show good agreement with theoretical results. An important conclusion is that the flexibility of the bottom rock must be included in order to predict resonant frequencies of the drillstring axial vibration.

• Journal of Radiation Protection and Research
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• v.31 no.1
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• pp.31-35
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• 2006

For the purpose of the biological effect in black mouse by neutron irradiation, mice were irradiated with 16 or 32 Gy neutron (flux: 1.036739E+09) by tying flat pose at BNCT facility on HANARO Reactor. And 90 days later of irradiation, physical changes of testis and testis tissue were examined. There were no weight changes but a little bit volume changes and sperm counts in the testes. Atrophy of seminiferous tubules irradiated with 32 Gy neutron is increased in number and severity and those in stage VI showed depletion of spermatogonia and pachytene spermatocytes compared to the non-irradiated control group. Testis damage of black mouse was not recovered after long time by 32 Gy neutron irradiation.

• Smart Media Journal
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• v.3 no.1
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• pp.39-45
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• 2014

The partial product matrix of a parallel squarer are symmetric about the diagonal. To reduce the number of partial product bits and the depth of partial product matrix, it can be typically folded, shifted and bit-rearranged. In this paper, an efficient design approach for the combined squarer, capable of operating on either unsigned or signed numbers based on a mode selection signal, is presented. By simulations, it is shown that the proposed combined squarers lead to up to 18% reduction in area, 11% reduction in propagation delay and 9% reduction in power consumption compared with the previous combined squarers.

• Journal of Korea Multimedia Society
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• v.5 no.4
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• pp.386-392
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• 2002

In this paper, we propose a novel blocking effect reduction method based on a rational B-spline. The blocking effect results from independent coding of each image block and becomes highly visible especially coded at very low bit rates. The proposed approach adopts a rational open uniform B-spline curve that used to produce a smooth curve through a set of control points. The pixels on the block boundary are treated as control points, and the weight values, which decide the shape of curve, are determined differentially by considering the distance the position of the pixels and that of the block boundary. The simulation results show that the proposed method has excellent performance for all pattern of the blocking effect with less computational complexity.

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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• 2021.05a
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• pp.204-206
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• 2021

Real-time drilling parameters prediction is a considerably important study from the viewpoint of maximizing drilling efficiency. Among the methods of maximizing drilling, the method of improving the drilling speed is common, which is related to the rate of penetration, drillstring rotational speed, weight on bit, and drilling mud flow rate. This study proposes a method of predicting the drilling rate, one of the real-time drilling parameters, using a recurrent neural network-based deep learning model, and compares the existing physical-based drilling rate prediction model with a prediction model using deep learning.

• Proceedings of the Korean Society For Composite Materials Conference
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• 2005.11a
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• pp.179-184
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• 2005

In the present study, conceptual design of the main wing for 20 seats WIG{wing in Ground Effect) flight vehicle, which will be a high speed maritime transportation system for the next generation, was performed. The high stiffness and strength Carbon-Epoxy material was used for the major structure and the skin-spar with a foam sandwich structural type was adopted for improvement of lightness and structural stability. As a design procedure for this study, firstly the design load was estimated with maximum flight load, and then flanges of the front and the rear spar from major bending load and the skin structure and the webs of the spars were preliminarily sized using the netting rules and the rule of mixture. In order to investigate the structural safety and stability, stress analysis was performed by Finite Element Codes such as NASTRAN/PA TRAN[6] and NISA II [7]. From the stress analysis results, it was confirmed that the upper skin structure between the front spar and rear spar was very unstable for the buckling. Therefore in order to solve this problem, a middle spar and the foam sandwich structure at the upper skin and the web were added. After design modification, even thought the designed wing weight was a little bit heavier than the target wing weight, the structural safety and stability of the final design feature was confirmed. Moreover, in order to fix the wing structure at the fuselage, the insert bolt type structure with six high strength bolts was adopted for easy assembly and removal.

• Elastomers and Composites
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• v.43 no.3
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• pp.183-190
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• 2008

In this study, we have investigated mechanical properties and scratch resistance of polypropylene compounds by two types of masterbatch with different molecular weight of PP. Masterbatches were prepared with polypropylene(PP) and polydimethylsiloxane(PDMS) by melt mixing. Mechanical properties and scratch behavior were examined with UTM and polarizing microscope. The morphology surface of grain pattern was investigated Color 3D Laser Scanning Microscope. Mechanical properties of two masterbatches containing PP compounds showed a little bit difference in accordance with amount of M/B. Scratch resistance was much improved by adding masterbatches used high-molecular weight PP. Scratch resistance was excellent when grain pattern of the surface is deep, large, round and irregular.